Time switch for adding machines



Get. '37 E T. S. BENDSCHEDLE ENG lMACHINES TME SWITCH FOR ADD Filed May 15, 1920 s sheets-sheet l Oct. 7, 1924.

` T. S. BKNDSCHEDLER lTIME SWITCH FOR ADDING MACHINES ms wm EN w w Oct. w24,

n. S. BINDSCHEDLER TIME SWITCH FOR ADDING MACHINES Filed May 13. 1920 3 Sheets-Sheet om Nm KNMNL mwN [NVE/VTOR ,4 TTOR/VEY Patented Oct. 7, 19h24.

. UNITED ISTATES PATENT OFFICE.)

THEoDoaE s. .ia1N1JscHiiD1.Eii.,v or Dmnorr, anonieme,` AssreNon. To BUnRoUGHs ADDING MACHINE coiErANY, or Dmnoxr, xrcHIeAN, A conPomrIoN or MICHIGAN.

TIME SWITCH For. ADDING MACHINES.

Application led Hay 18,

To all whom. it may concern:

Be it known that l, THEODORE S. BIND- soHEDLER, a citizen of Switzerland, residing at Detroit, in the county of Wayne, State of Michigan, have invented certain new and useful Improvements in TimeSwitches for Adding Machines, of which the following is a specification.

My invention relates to adding machines driven by continuously rotating motors, a type of which is shown in patent to Vincent, No. 866,750 issued September 24, 1907. In such electric driven adding machines the rock shaft by the operation of which a number set up on the keyboard is carried into the machine is oscillated from a rotary shaft which-is given a complete rotation for this purpose whenever the clutch intermediate said Vshaft and the continuously running electric motor is thrown into engagement after the desired number isset up in the machine, b the depression of its finger-bar. -Obvious y, it is essential that the motor circuit remain closed as long as the machine is in use and an ordinary switch will serve for this purpose. It frequently happens, however. where a hand-switch is employed that it is inadvertently left in the` closed position after the operator has finished using the machine, with the result that there is a considerable waste of current and useless wear upon the motor. Prior to my invention efforts have been made with more or less success to provide a means by which the motor circuit is automatically opened within a definite period after the last number is carried into the machine. An example of such a construction isshown in patent to Rinsche, No. 1,310,965, granted July 22, 1919. In the machine4 of said Rinsche patent the depression of the finger-bar for-closing the clutch to o rate the mechanism for carrying the numhr set up into the machine trips a. timing mechanism which, after a desired period opens themotor switch unless in the meantime the linger-bai is 'again operated to trip said mechanism. The time within which the V mechanism opens the switch is controlled by a dash-pot. My invention is inlthe nature of an improvement upon the time switch disclosed invs'aid Rinsche patent in which the dalsli-po'is dispensed withgand the time switch more certainly and accuratel 'controlled by thermostatic-means, thus e acting 19.20. Serial No. 381,088.

an' increased saving in current consumption iandalso more completely protecting the mo- In the accompanying drawin I have shown and in the following s e'ci cation described in detail a preferred orm of my invention.A It is to be understood, however,

that the specific disclosure is for the purpose of exemplifcation onlv and that the scope of the invention is set forth in the following' claims in which I have endeavored to distinguish my invention vfrom the prior art so far as known to me without however relinquishing or abandoning any portion or feature thereof. In the drawings Fig. 1 is a vertical section'on an enlar ed scale through the casing of a time switch embodying my invention, the switch'itself beingl shownin elevation and in the o en position; Fig. 2 an elevation of the switc upartly in section,` the contacts being shown closed; Fig. 3 a vertical section on a plane parallel to the plane of Figs. l and 2; Fig. 4 an enlarged verticalsection of the thermostat element partly brokenA away in the center; Fig. 5 a side elevation at right angles to Figs. 1, 2 and 3 partly in vertical section; Fig.'l 6 a detail elevation of certain parts from the same point of view as Figs. 1, 2 and 3 but with the parts in different positions; Fig. 7 a horizontal sectional view on the line 7-7 of Fig. 1; Fig.

8 a horizontal section on the line 8 8 o'f Fig. 1 with parts broken away to more clearly illustrate the construction; Fig. 9 a detail perspective of the thermostat switch; Fig. 10 a wiring diagram of the switch, and F ig.' 11 an enlarged vertical section of a detail on the line 11-11 of Fig. 1. v

Each part is identified by the same reference character wherever it occurs throughout the several views.

In the preferred form of my invention shownin the Llrawings and hereinafter described itis applied to a yswitch of the same character, exce t as hereinafter speci-fied, as that illustrated) in said Rinsche patent and therefor I have-deemed it unnecessary to indicate herein the adding machine proper, the

motor and the clutchjfor effecting driving connection between the` motor and the mechanism of the addng-machine, and in so far as the rconstruction of my present invention is common also Atd'the .Rinsche/ construction aforesaid, it will be but briefly described as for controlling the clutch, not shown, and

24 is a mutilated gear thereon which meshes with a similar gear 25 upon an arm 26 which is raised when the finger-bar above mentioned is depressed by the operator. A rod 27 extending through a loop 26a and more ful/ly shown and described in said Rinsche 'atent communicates motion from the fingerhar to arm 26. Binding posts 30, 31 are con-l nected by conductors in the cord 29 to a suitable source of current. To the binding post 30 is also secured the end 32 of one of the conductors leading to the motor, the other of which conductor is connected to the binding post 33. The binding posts 31 and 33 are connected respectively to the plate springs 35, 34 of a knife switch, the movable knife 36 of which is carried by but insulated from an arm 37 pivoted upon a stud 38 secured to the casing 39 of the clutch. (See Figs. l 5 and 7.) A. convenient means for securing the knife upon the lever 37 is a stud 40 projecting from the face of said lever surrounded by an insulating bushing 40 extending through the knife 36, the stud and bushing projecting through a circular opening vin the knife. A plate spring 4l riveted to the lever at 42 holds the knife in place on the stud and bushing, it being understood, of course, that there is suitable in sulation 40b between the lever and spring and said knife. The knife is free to turn within a small angle to accommodate itself to the contact springs. To the arm 37a of said lever 37 is connected a spring 46 the other end of which is attached to a stud 47 upon the framework so that said spring tends to throw the lever carrying the knife toward the contact springs 34, 35. vAs seen in Fig. l, however, the lever 37 is normally held in open osition by a latch 48 which engages the s ulder or abutment 49 upon the lever for-.this purpose. The' spring 50 con,- nected to the stud 47 and to the tail of the latch 48 maintains the latter in contact with the shoulder on the lever. ylhe tail 51 of the latch extends into the path of movement of the washer 52 secured to the lower end of the rod 27 heretofore described as constituting a part of the clutch controlling mechanism, so that when said rodi's `raised by the depres-v sion of the nger-bar it engages and trips the latch 43 permitting the lever 37 to be swung by s ring 46 to close the switch. 'lthe closing of t e switch completing the circuit through the motor energizes the latter and it continues inr 4operation until the knife inafter described;

switch is again opened in the mannerhere- Leider? Provision is made for moving the latch to a position in which, (unless it be again tripped by the movement of the bar 27) it will again pick up the lever 37 and restore it to the open position. With this in view said vlatch is ivoted at upon a T-shaped lever 66 whic is likewise fulcrumed upon the stud or-post 38; see Figs. 1 and 7. The T- lever is normally maintained in the open position shown in Fig. 1 by a spring 67 secured to the arm 66b of said lever and to stationary stud 67a. Movement of the T-lever under the impulse of spring 67 is limited by a latch 72 hereinafter described which, together with the spring normally holds the T-lever in the position shown in Fig. l in which the pawl or latch 48 maintains the knife-carrying lever 37 in open position. Latch 72 is pivoted at 73 and capable of a slight oscillation vertically about said pivot, and its lower edge is of irregular shape providing two shoulders 74, 75 which respectively engage andL hold the in-turned end 76 of the downwardly extending arm 71 of the T-lever in vits normal and retracted positions, (Figs 1 and 2) respectively. As heretofore stated, the normal position is shown in Fig. l1. The engagement of arm 71 with shoulder 75 is shown in Figs. 2 and 3. Obviously when the latch 48 is tripped to release the lever 37 to close the 'switch as hereinbefore described, the shoulder 49 slips by above the engaging shoulder of the latch; and in order toreenga e the latch and shoulder. the former is raise by oscillating the T-lever slightly about its pivot to the position shown in Fig. 2 in which the latch 1s again engaged with the shoulder of lever 37 without however movingl lever 37 from the closed position.

` The means for effecting the above described oscillation of the T-lever to again engagethe latch and contact` lever will now be described. 0n the end of shaft 9, which as described in theabove-mentioned Rinsche patent is given a complete revolution by the motor when the clutch is engaged, is a snail cam 53 and the latter engages a friction roll 54 upon a four-armed lever 55 which is pivoted upon the same post or stud 38 upon which levers 37 and A66 are pivoted; .see

Figs. l, 2 and 7. Spring 64 (see Fig. 5) connected to arm 55m of the four-armedlever maintains the roller 54 in engagement with snail cam 53. bViouSly, as thesnail cam is revolved by the motor, lever 55 is oscillated about its pivot, the arm bearing the roller 54 being alternately depressed and permitted to riser under the impulse of the spring 64.` rl"he downwardly projecting arm 55b of said lever carries a in or stud 70 which projects forwardly an in -advance of the' ed e of the/aforementioned arm 7l of the' lfever,` andwhen the roller 54 is de pressed by the snail cam, stud 70 operates against the edge of arm 7l forcing the latter lSUf to the left 4(as seen in the Fig. 2) and into a position to be engaged by the shoulder on latch 72. A spring 7 2a connected at oneA end to a lug 72b on said latch and, at the other to a stationary stud 72c lowers latch 72 into position for the shoulder 75 to engage the in-turned end 76 of arm 71 when the latter is moved to the left by the action of the snail cam, as above described. Obviously, so long as the parts remain in the position shown in Fig. 2 with the lower end of the arm 71 engaged by the shoulder 75 on latch 72, the switch remains closed even though the latch 48 is in engagement with the shoulder 49 upon lever 37. Provision is made, however, for the release of arm 71 by latch 72 and the restoration of the parts to normal condition when the linger-bar and consequently bar 27 by which latch 48 is operated remain idle.and the clutch open for a certain pre-determined period.

The construction as described up to this point is substantially the same as that disclosed in the Rinsche patent aforesaid, but the means for restoring the parts to normal position which will now be described is entirely different from the dash-pot controlled means of said patent. It comprises la ther` mostatic bar a, controlling the opening of the switch and surrounded by a heating coil 124 and a thermostat switch b governing the supply of current to the coil surrounding the thermostatic bar, the construction being such that as long as the machine is operated at pre-determined intervals, the thermostat will be maintained heated above the critical temperature, but as soon as the machine has been idle beyond the pre-determined period the thermostatic bar cools oii and opens the contacts of the motor switch. For thispurpose the thermostat bar comprising, as usual, two strips of metal 80, 81, of unequal coefficients of expansion is anchored at its upper end as by screws 82 to a stationary portion of the frame. To the lower end of the thermostat, as at 83, is pivoted a cam link 84 which, as the thermostat warps under the influenceof heat, is carried back and forth from the position shown in Fig. 2 to that 'shown in Fig. 3, solid lines. The left-hand end of cam link 84-is 11p-turned as at 85 and connected by a spring 86 to a stud 47 so that said end of the link is always urged upward. The upper edge of the cam link is formed at 88 with a hump 'for the purpose of rocking the rocker 89 as will presently appear. Said rocker is fulcrumed at 90 and carries at one end a stud 91 having an insulating covering which engages the movable contact 92 of the thermostatswitch to close the circuit of the thermostat coil in a man ner which will presently be described. For

the present purpose it is sufficient to understand that when contact 92 is forced upward by the stud 91 the thermostat isvheated and warped out of the position shown in Fig. 2 in the direction indicated in Fig. 3. Normally the rocker 89 is in the position shown in Fig. 1 and the tail 93 thereof is swung to the right as viewed in said figure, so that the V-shaped end 94 thereof is a trifle to the right of the apex 95 of the hump 88 on the cam link. In this normal position of the parts the outwardly turned end 96 of the right-hand arm of the rocker is in contact with the finger 97 of bell-crank lever 98 which is pivoted onstud 38, thus limiting the movement of said. bell-crank lever under the impulse of its spring 99. (See Figs. 1 and 3.) Bell-crank 98 is swung to the left against the tension of its spring 99 when the machine is operated, the four-armed lever 55 being provided for this purpose with a stud 100 which engages the edge of said bellcrank lever when the four-armed lever is i operatedby the snail cam. The effect of the movement of the bell-crank lever to the left is to cause the cam surface 101 thereof to wipe along the outward turned end 96 of the rocker, depressing said end thereo.' and forc- J ing the tail of the rocker to the left, so that the apex thereof passes the apex 95 of the hump 88 on the cam link. When this occurs the pull of spring 86 draws 'the cam link upward, completing the movement of the rocker so that the insulated stud 91 thereon engages the movable contact 92 and closes the circuit through the coil of the thermostat. (See Fig. 2.) This occurs during the initial movement of the four-armed lever 55 under the action of the snail cam and before said lever engages and moves the arm 71 of T-lever 66. T he furthery .movement of leverl 55 under the influence of the cam as the highest point of the latter reaches the roller brings the parts to the position shown in Fig. 2 in which the thermostat contacts re. main closed and the 'lever 66 is locked in position by engagement of the arm-71 with the shoulder 75 of latch 72. The thermostat now begins to heat up and to move the cam link 84 to the left, the hump 88 thereof wiping under the tailfof the rocker until the apex of the hump passes the point of the tail of the rocker, when the cam surfaces of these parts under theftension of the spring 86 causes the rocker to swing back into the position which it is shown as occupying in Fig. 3, and in which the contacts of the thermostat are permitted to open. The thermostatic bar now begins to cool ofi` and consequently the cam link moves toward the rght; the arm 71 is, however, still held by the shoulder 75 of latch 72. If no other items are entered in the machine, as the thermostat continues to cool and approaches its ultimate' position, latch 72 is raised to rei and, the latch 48 being in `engagement with the shoulder 49 on the contact lever, to open the contact. A

The release of the arm -71from latch 72 is brought about by the following construction and operation. Said latch carries a trip lever 105 pivoted thereto near its free end by a pin and slot connection 106 so that said lever has not only a swinging buta slight reciprocating movement relative to said latch. A spring 107 connected to a lug 108 on said trip and astud 109 on the latch normally draws the trip to the left, asl

seen in Fig. 3. (See also Figs. 1 and 8.) Said trip isalso formed at its ri ht-hand end with an inwardly extending ger 110'for a purpose which will appear. Upon the same stud 106 upon which thetrip works is pivoted a trigger 112 formed with a shoulder .113 which is directly beneath the finger 110 when the trip is in its left-hand position, but is cleared by said finger wheny the trip is in its right-hand position. The left-hand end of the trip is formed with a lip 114 which projects into the notch in latch 72 in advance of the shoulder 75. The purpose of the trip and trigger is to release the arm 71` from the latch 2 at the proper time. The trip being drawn forward under' the control ofits spring andthe inwardly projecting end of arm 71 beingA against the shoulder 7 5 and beneath lthe lip on said trip, and the iinger of the trip belng immediately above the shoulder upon the trigger, when the latter is drawn to the right, as seen in the several figures as the thermostat cools o and thereby swung about its pivot, the shoulder on the trigger engages the linger on the trip causing the latterto tilt downward at its left end and to en age the inwardly projecting end of arm rl"his lifts the latch 72 in an obvious manner and releases the arm so that the lever- 66 carrying the pawl 48 is restored to normal position and carries the contact lever therewith, thusbpening the circuit. As the arm 71 swings to the ri ht it engages the downwardly extending e ge 116 of the trip and carries the latter with it so that the nger on the trip then clears the shoulder on the trigger.

As best seen 1in 1, 2 and 3, the lower l end of the trigger is cam shaped andextends between a st 117 and a boss 11,8 on a bracket 1,19 secured to the lower end of the thermostaxtic bar. As the thermostat warps and the cam link is carried to the left the trig er is engaged by the stud 117 and swung to t e left, taking the shoulder out of the way of the finger 110 u on the trip. As the thermostat cools off an carries the cam link to-the right the trig er is engaged by the boss 118 and swung aiout its pivot and the finger 110 being at this time directly above the shoulder of the trig er, the trip is tilted P as above descri to re the latch from the arm 71. Thus in the event that there is no succeeding operation of the adding ma.-

chinevwhile the thermostat is cooling off, the

'depressed as usual in motor-operated machines, raising the vertical bar 27 operating the clutch mechanism and tripping the latch 48. This permits the switch arm 37 to carry the'knife into engagement with the contacts 34 and 35, thus closing the circuit through the motor and operating the latter and at the sanie Itimecarrying the shoulder 49 above the ceoperating shoulder upon the latch. The shaft 9 carrying the snail cam 53 then revolves, the latter engaging the roller 54 upon the lever 55, rocking the latter about the stud 38 and causing the stud 100 to engage the bell-crank lever 98, swinging the latter about its ulcrum 38. This causes lever 98 to depress the right arm of the rocker swinging the tail of the latter to the left, past the apex of the hump of the cam link, when the upward. tension on the latter completes the' rocking of the rocker so that it closes the circuit of the thermostat coil. The further movement of the lever 55 oscillates the T- lever clockwise to the position in which it is engaged by the shoulder 75 on latch 72 and theg pawl 48 engages shoulder 49 on the contact lever. Thethermostat warps to the left 'and if no more items are entered into the machine, as the apex of the hump on the cam lever passes the tail of the rocker, the. tension of the spring 86 lifting the cam link rocks the rocker 'fto open the thermostat circuit. During this movement to the left the trigger is swung and the trip also moves to the left so 'that the finger on the latter is over the shoulder on the former. After the thermostat begins to cool, however, the movement of the bracket carried thereby to the right swin the trigger, tilting the trip, raising the latch 72 and thereby releasing the arm 71 so that the parts return lto the normal position shown in Fig. 1.

The previously described operation presupposes that no additional items are put in the machine after the rst operation. lf, however, additional items are put in the machine and the bar 27 depressed to enter the items in the machine, the clutchkwill be engaged and the snail will again revolve, oscillating the lever 55. If this occurs before the thermostat has cooled sufficiently to release fthe arm 71 from the shoulder 75, the oscillation oflever 55 has no effect on the latter. The bell-crank 98,-however, is a ain operated .and on its return the offset en 96 of lever 89 is caught on the Shoulder 98'L of covered by asbestos cord 124B.

lever 98, so that the rocker 89 is not oscillated sufciently to again close the thermostat circuit. This condition of the parts is represented in Fig. 6. As the thermostat continues to cool off, however, ultimately the hump 88 wipes past the end of the tail of the rocker which is prevented from swinging to the position shown in Fig. 1 by engagement with the bell-crank lever) and the upward movement of the cam link under the inlinencc of its spring again shifts the rocker to close the thermostat circuit. By reason of the last described feature of the construction whereby the thermostat circuit is not closed throughout the full unwarping action of the thermostat a large amount of wear on the thermostat and its switch is avoided.

In order to insure proper adjustment of the parts in assembling, a lever 121 is pivoted on the same stud 83 which carries the cam link, the forward end of said lever 121 being slotted to engage the stud 72C above mentioned. As shown in Fig. 1, the slot 122 engaging said stud limits the movement of the parts connected to the lower end of the thermostat element to the right, and thus acts to position the parts with the apices of -the hump of the cam link and nose of the rocker in the normal position shown in Fig. 1 when assembling.

I shall now describe the details of the thermostat and of the electric system by which it is heated, including the switch, heretofore referred to in a more I`general way as operated by the rocker 89, though it is to be understood that the specific construction shown, while satisfactory, need not be adopted in detail. The construction of the thermostatic element may best be understood in connection with Figs. 2, 3 and 4. The` thermostatic element proper, a, may be formed of two strips of metals of unequal expansion, such as brass and steel, preferably cemented or solderedtogether as usual in such .elements. In Fig. 4, which shows the thermostat on a very much enlarged scale, the

strip is represented as reduced intermediate its ends at 123 to reive theheating coil 124, the latter being of insulated wire and The ends of the coil are connected to terminals 125, 126, extendin into a block of insulating material 125% andg secured to, but insulated from the tang by rivets 127, 128 respectively. Terminal is connected to post 30 by wire 125. A cover plate 129 is secured by the screws 82, previously described. Referring to Fig. 10, which shows the wiring, 29", 29h, represent connections from the source of current to the posts 30, 31. The motor circuit is included between the t 30 and post 33, the motor being shown iigrammatically at f. Knife 36, as heretofore described, closes the motor circuit when permitted to close. It also closes the heating circuit for the thermostat except for the thermostatic switch b which is subsequently closed by the operation of the time switch as heretofore described.

The details of the thermostat switch are best shown in Figs. 9 and 11. As seen in said figures, a small casting is formed with the hollow screw-threaded shank 131 which is adapted to receive a nut 132. An insulated conductor 133 extends through the hollow of theJ bolt and is soldered or otherwise secured at its inner end to a spring plate 134 carrying the spring terminal 135. Said plate 134 and terminal 135 are insulated from the casting by a suitable insulating washer 136 and secured in position in a cutout portion of the casting by means of an insulated bolt 137. The movable contact member consists in a short sliding rod 92 extending into `a transverse bore 139 in the casting, said bore being enlarged at 140 to receive a spring 141 which engages a collar 142 on the rod `and a washer 143, between which collar and washer the spring is compressed so that it normally forces the contact outwardly. The entire construction is enclosed in an insulating casing 145 and insulated at 146 from the frame. Connection to the movable contact 92 is made by means of a wire 150 clamped between said nut-132 and a washer 151 on the threaded shank of said casting.

In order to trip the latch 72 by hand when desired, it is formed with a heel 152 which extends into the path of a plunger 153 slidingly mounted in a bore 154 in the casing. A spring 155 compressed between the shoulder in the bore and the finger-piece 156 on the plunger normally maintains the latter in outer position, see Fig. 1. To lift the latch it is only necessary to push the finger-piece of the plunger, but the latter is normally out of the. way and does not in'- terfere with the automatic operation of the device.

I claim: 1. In a time switch for controllin the circuit of a motor for operatin ad ing machines and the like having a c utch for controlling the operation of the adding machine by the motor, manually operated means for tripping the switch to close the. latter, means for opening the switch after an actuation of the clutch, and a thermostat controlling the last said means.

2. In a time switch for controlling the circuit of a motor for addingl machines and the like having a clutch for controllin the operation ofthe adding machine by t e motor,

lll

a shaft adapted to be revolved by the motor, 1'35 means for closing the switch, manipulative means for releasing the closing means, means operated by said shaft for opening the switch, and a thermostat controlling the last said means.

- the like, a rotary shaft, means for closing' 3. lin a time switch for controlling the circuit of a motor for adding machines and the switch, a latch normally restraining said means, 'manipulative means for releasing the latch, means operated by said shaft to open the switch, a thermostat controlling the last said means, electric heating ineans for said thermostat, and means operated by said shaft toriclosing the circuit or' said electric heating means. l

4. In a time switch for controlling the circuit of a motor for adding machines and the like, a rotary shaft, a stationary7 contact, a movable contact, an arm carrying said movable contact, a spring for moving Said arm toclose the switch, a latch .for holding the arm in open position against .the pressure of said spring, manipulative means for tripping the latch to release said arm, mealns operated by said shaft for reengaging the latch and arm, a second latch forpreventing the restoration of said contact arm to opened position, means for tripping said second latch, and a thermostat controlling the last said means.

ln a time switch for controlling the 'circuit of a motor for adding machines and the like, a shaft adapted to be rotated by the motor, afstationary contact, a movable contact, an arm carrying'the latter, a spring moving said arm to close the switch, a latch for hdlding the arm in open position, manipulative means for tripping the latch, a lever carrying said latc means operated by said shaft for shifting said lever to permit the latch to re-engage the contact-carry-v ing arm, a second latch for holding said lever in shiftedmposition, a thermostat, means carried by the thermostat for tripping the second said latch, electric heating means for the thermostat, a switch in the circuit of saidelectric heatin means, and means operated by said sha for closing.n said switch.

6. ln a time switch for controlling the ciry cuit ot a motor for adding machines and the like, a shaft adapted tov be operated by the motor, 'a stationary and a movable contact, an arm carrying the latter, a spring for moving said arm to close the switch, a latch for holding the arm in open position, manipulative 'means to release the latch, a lever to which said latch is pivoted, means 'for moving said lever. :from normal position to a position to permit said latch to re-engage the contact-carrying arm, means for restoring said lever to normal position, a latch onpreventing the return of the lever to normal position, a thermostat, means operated by the thermostat foi1I- tripping the latter said latch to permit said lever` to return to normal position, electric means for heatin the thermostat, and av switch tor contro ling said heating means.

ramer? the latch, a lever carrying the latch, means for normally holding Athe lever in position` such. that the latch when engaged with the contact arm holds the latterin open position, a cam carried bysaid shaft, means operated by the cam formovingsaid lever to a position to re-engage the latch with the contact-carryingv arm when hc latter is in closed position, a latch for preventing the return of thelever to normal position, a thermostatic bar secured at one end to the framework of the switch, a trip lever for disengaging the second said latch from the latch-carrying lever, a trigger engaged by the thermostat for operating the trip lever, a coil for heating the thermostat, a switch in the circuit of said coil, and means for opening and closing said switch.

8. ln a time switch` Jfor controlling the circuit of motor for adding machines and the like,Y a shaft, stationary and movable contacts, an arm carrying said movable contact, a spring for'moving said arm to close the switch, a latch for holding the arm in open plosition, manipulative means for tri ping t e latch, to permit the arm to close t e contact, a lever carrying the latch, a spring' tending to move the. lever to normal position, a cam carried by said shaft, means ini re-engage the contact-carrying arm in closed position, a latch to restrain the lever from return to normal position, a thermostat, means operated by the thermostat to trip the latch and permit the return of the lever to normal position, electric heating means :tor heating the thermostat, a switch'in the circuit of said electric heating means, a rocker for closing the'last said switch, means operated by said 'shaft for rocking said rocker. l ln I V9,. ln a timeswitoli for controlling the circuit of a motor, a stationary and-a movable contact, an arm 37 carryingfthe movable contact, a latch 48 for holding the arm in' open position, manipulative means for trippingthe latch, alever 66 on which said latch is ivoted, a spring 67 tending to restore sai lever to normal position, a shaft, a cam 53 carried by said shalt, a lever 55 rocked by said cam, means on vthe lever 55 for engaging ylever 66 to swing the latter to a position in which the latch can re-engage arm 37, a latch 72 adapted to hold the lever 66 in the last said position, a trip on the last said latch adapted to rock and to disengage Said' latch from the lever 66, a `trigger 112 adapted to engage and rock the trip, a thermostat bar secured. at one end to the frame- Work and having means to en age and operate the trigger, electric heatmg means for the thermostat, a switch in the circuit of said electric heating means, and means operated b said cam 53 for closing the switch of saidv e ectric heating means. 4

10. Ina time switch for controlling the circuit of a motor for adding machines and the like, a stationary and a movable contact, an arm carrying said movable contact, a spring for moving said arm to close the switch, manipulative means for permitting the arm to close the contacts, means including a thermostat for governing the opening of the contacts, a coil surrounding the thermostat, a circuit for said coil including a source of current and a switch, means set in motion by said manipulative means for closing the last said switch.

11. In a time switch for controlling the circuit of a motor for adding machines, a stationary and a movable contact, an arm 37 carrying the latter, a sprin impelling saidl arm to close the switch, a atch 48 for engaging the varm and holding the switch open, a lever 66 carrying the latch, a spring tending to move the lever 66 to normal` position, a cam 53 on said shaft, a lever 55 .operated by the cam, a stud on the lever 55 to engage lever 66 and bring the latter to a position to permit latch 48 to re-engage arm 37 when in closed position, a second latch for maintaining lever 66 in the last said position, a thermostat, electric means for heating the thermostat, a circuit for said electric means, a switch for controlling said circuit, means controlled by said thermostat for closing and openin` the last said switch.

12. In a device of t e class described, a switch having a stationary and a movable contact, an arm carrying the movable contact, means for swinging the arm in a direction to close the switch, means ada ted to be operated by the motor controllo by the switch for opening the switch, a thermostat, electric means for heating the thermostat, a circuit therefor controlled by said switch, and means controlled by the thermostat for preventing the operation of the switch-opening means for a predetermined period.

i3. In a device of the class described, a

lswitch controlling a motor circuit, a catch for holding the switch open, a device for tripping the catch to close the switch, a cam for re-setting the switch in open position, a thermostat, electric means for heating the thermostat, a circuit therefor .ccn-

troiled hy said switch, and means controlled by the termostat for preventing the operation ofthe switch-opening means for a predetermined period.

14. In a device of the class described, a switch for controlling the circuit of a motor, a catch normally holding the switch in open position, mani ulative means for releasing the catch an permitting the switch to close, a cam adapted to be operated by the motor, a lever operated by the cam for resetting the switch in open position, a thermostatic element, a latch controlled thereby for holding the lever inoperative, electric heating means for heating the latter, the circuit of said electric heating means controlled by the switch, asecond switch in the circuit of the electric heating means, lmeans operated by said cam for closing the last said switch.

15. In a time switch for opening the circuit of 'a motor operated adding machine and the like, including a movable contact for closing the motor circuit, a catch normallyi holding said Contact in open position, manipulative means to trip the catch and permit the said contact to close the switch, means for moving said contact to closed pitiom-means :tor restoring the contact to open position, a latch for preventing the return of the Contact to .open position, a thermostat, an electric heating means therefor, a circuit for said means, a switch for said circuit, means for closing the last said switch controlled by said thermostat. Y

16. A time switch for opening the circuit of a motor-operatedadding machine or the like, including a movable contact for closing the motor circuit, an arm carrying said contact a catch normally engaging the arm and holdinr the contact in open position and arranged5 to be tripped by the manipulative means to release the arm, a spring tending to move the arm to close the switch, a cam adapted to be driven by said shaft, a second lever having an arm extending into the path of said cam to be swung thereby, means on the second lever to engage the first lever and swing it to a position in which the catch thereon may engage the contact carryving arm when the latter is in closed position, a spring tending to restore the catch carrying lever to normal position, a latch adapted to engage the last said lever when the latter is moved from normal position and prevent its return to normal position, means for releasing the liever from the latch comprising a thermostat, electric heating means for the thermostat, and a circuit for the electric heating means controlled by said switch.

THEUDORE Si. BENDSCHEDLER, 

